Chemistry
Ammonia solution in water gives a blue precipitate when it combines with a solution of copper salt. The blue precipitate further dissolves in excess of ammonia solution to give an azure blue solution. Explain with equation.
Ammonia
Answer
Ammonia solution in water gives a blue precipitate when it combines with a solution of copper salt, due to the formation of Cu(OH)2
CuSO4 + 2NH4OH ⟶ (NH4)2SO4 + Cu(OH)2 ↓
The pale blue precipitate of copper hydroxide dissolves in excess of ammonium hydroxide forming tetraamine copper [II] sulphate, an azure blue soluble complex salt.
Cu(OH)2 + (NH4)2SO4 + 2NH4OH ⟶ [Cu(NH3)4]SO4 + 4H2O
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(d) Aqueous solution of ammonia conducts electricity.
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